| 摘要 |
<p>Downhole tools that have a housing, a linearly indexing driver, a reciprocating shifter, and an actuation seat. The driver is adapted for linear indexing relative to the housing from an initial position sequentially through one or more intermediate positions to a terminal position. The shifter is adapted for axial reciprocation relative to the housing and is operatively connected to the driver and adapted to index the indexed driver from its initial position sequentially through its intermediate positions to its terminal position as the shifter reciprocates. The actuation seat is mounted on the shifter and is adapted to receive a ball for actuation of the shifter and to release the ball after the shifter has indexed the indexed driver. Thus, a series of such tools may be operated by deploying a series of balls, all of the same size, through the tools.</p> |
